The dramatic increase in the use of interventional spine procedures and the rising health care costs over the past decade have raised lots of questions about the utilization and outcomes of treatments for back and neck pain. Several articles have addressed some concerning scenarios related to spinal surgeries and catastrophic adverse events after epidural steroid injections have been reported, related to steroid use. The purpose of this study is to describe and characterize the treatment of back and neck pain, while examining temporal and geographical trends, physician specialty, and setting variations. We will characterize treatment trajectories in newly diagnosed back and neck pain patients and identify efficient treatment paths and potential gateways to high cost and utilization. The characterization of patients treatment paths will include tracking of manual and percutaneous treatments, use of opioids, imaging utilization, surgical procedures, and safety events. We will examine the outcomes and adverse events following interventional spinal procedures by tracking patients for at least one year after their procedures. Identifying efficient and safe treatment paths for back pain will lead to better guidelines for back pain management. A characterization of the outcomes and side effects of interventional spinal procedures will help patients and physicians make more informed decisions about treatment options. Data This project currently focuses on Medicare administrative health records for patients diagnosed with back pain between 2000-2013. An interagency agreement to access these data has been established between NIH and CMS. Since the previous annual report, we have achieved the following: Renewed our seat for access to a CMS virtual research data center (VRDC) that allows the analysis of CMS data in SAS, on CMS servers. Produced preliminary results based on a subset of the data of interest and evaluated the feasibility of future work. Revising a manuscript for resubmission. Continued collaborations with academic partners. Identified codes of diagnoses, procedures, drugs, complications, and outcomes relevant to our projects. Additional data runs have been conducted on the updated dataset and cohort that focus on patient demographics and numbers of injections over the period under study. Differential complication rates by steroid type and injection approach are being examined. A published analysis explored the use of injections, surgical interventions, and physical therapy utilization in a sub-cohort of patients with spondylolisthesis. Preliminary results have been presented at Grand Rounds style conferences.